Field of the Invention
The present invention relates to a differential mode filter and, more particularly to a differential mode filter excellent in high-frequency characteristics.
Description of Related Art
A differential mode filter is used as a device passing a common mode component on a differential signal line therethrough while blocking a differential mode component (see Japanese Patent Application Laid-open Nos. 2007-036158 and 2010-165953).
As described in Japanese Patent Application Laid-open Nos. 2007-036158 and 2010-165953, in the differential mode filter, a pair of wires are wound in opposite directions, so that they cross each other a plurality of times on a winding core. This is a structural feature of the differential mode filter.
In the differential mode filters described in Japanese Patent Application Laid-open Nos. 2007-036158 and 2010-165953, the crossing angle between a pair of wires is kept constant (see FIG. 5 of Japanese Patent Application Laid-open No. 2007-036158 and FIG. 2 of Japanese Patent Application Laid-open No. 2010-165953). However, when the crossing angle between the wires is made constant, high-frequency characteristics may be degraded by a capacitance component between the wires and terminal electrodes.